CsvSchema (Jackson-dataformat-CSV 2.5.0 API)

java.lang.Object
- com.fasterxml.jackson.dataformat.csv.CsvSchema

All Implemented Interfaces:

com.fasterxml.jackson.core.FormatSchema, Serializable, Iterable<CsvSchema.Column>
```
public class CsvSchema
extends Object
implements com.fasterxml.jackson.core.FormatSchema, Iterable<CsvSchema.Column>, Serializable
```
Simple FormatSchema sub-type that defines properties of a CSV document to read or write. Properties supported currently are:
- columns (List of ColumnDef) [default: empty List]: Ordered list of columns (which may be empty, see below). Each column has name (mandatory) as well as type (optional; if not defined, defaults to "String"). Note that
- useHeader (boolean) [default: false]: whether the first line of physical document defines column names (true) or not (false): if enabled, parser will take first-line values to define column names; and generator will output column names as the first line
- quoteChar (char) [default: double-quote ('")]: character used for quoting values that contain quote characters or linefeeds.
- columnSeparator (char) [default: comma (',')]: character used to separate values. Other commonly used values include tab ('\t') and pipe ('|')
- lineSeparator (String) [default: "\n"]: character used to separate data rows. Only used by generator; parser accepts three standard linefeeds ("\r", "\r\n", "\n").
- escapeChar (int) [default: -1 meaning "none"]: character, if any, used to escape values. Most commonly defined as backslash ('\'). Only used by parser; generator only uses quoting, including doubling up of quotes to indicate quote char itself.
- skipFirstDataRow (boolean) [default: false]: whether the first data line (either first line of the document, if useHeader=false, or second, if useHeader=true) should be completely ignored by parser. Needed to support CSV-like file formats that include additional non-data content before real data begins (specifically some database dumps do this)
- nullValue (String) [default: "" (empty String)]: When asked to write Java `null`, this String value will be used instead.
  NOTE: NOT used for reading at this point (this may change in future)
Note that schemas without any columns are legal, but if no columns are added, behavior of parser/generator is usually different and content will be exposed as logical Arrays instead of Objects.
There are 4 ways to create CsvSchema instances:
- Manually build one, using CsvSchema.Builder
- Modify existing schema (using withXxx methods or rebuild() for creating CsvSchema.Builder)
- Create schema based on a POJO definition (Class), using CsvMapper methods like CsvMapper.schemaFor(java.lang.Class).
- Request that CsvParser reads schema from the first line: enable "useHeader" property for the initial schema, and let parser read column names from the document itself.
See Also:
Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`CsvSchema.Builder` Class used for building `CsvSchema` instances.
`static class`	`CsvSchema.Column` Representation of info for a single column
`static class`	`CsvSchema.ColumnType` Enumeration that defines optional type indicators that can be passed with schema.

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`_arrayElementSeparator`
`protected CsvSchema.Column[]`	`_columns` Column definitions, needed for optional header and/or mapping of field names to column positions.
`protected Map<String,CsvSchema.Column>`	`_columnsByName`
`protected char`	`_columnSeparator`
`protected int`	`_escapeChar`
`protected int`	`_features` Bitflag for general-purpose on/off features.
`protected char[]`	`_lineSeparator`
`protected char[]`	`_nullValue`
`protected int`	`_quoteChar`
`static char`	`DEFAULT_ARRAY_ELEMENT_SEPARATOR` Default separator for array elements within a column value is semicolon.
`static char`	`DEFAULT_COLUMN_SEPARATOR` Default separator for column values is comma (hence "Comma-Separated Values")
`static int`	`DEFAULT_ESCAPE_CHAR` By default, no escape character is used -- this is denoted by int value that does not map to a valid character
`protected static int`	`DEFAULT_FEATURES`
`static char[]`	`DEFAULT_LINEFEED`
`static char[]`	`DEFAULT_NULL_VALUE` By default, nulls are written as empty Strings ("")
`static char`	`DEFAULT_QUOTE_CHAR`
`static boolean`	`DEFAULT_SKIP_FIRST_DATA_ROW`
`static boolean`	`DEFAULT_USE_HEADER` By default we do NOT expect the first line to be header.
`protected static int`	`FEATURE_ALLOW_COMMENTS`
`protected static int`	`FEATURE_SKIP_FIRST_DATA_ROW`
`protected static int`	`FEATURE_USE_HEADER`
`protected static CsvSchema.Column[]`	`NO_COLUMNS`

Constructor Summary

Constructors
Modifier	Constructor and Description
	`CsvSchema(CsvSchema.Column[] columns, boolean useHeader, boolean skipFirstDataRow, char columnSeparator, int quoteChar, int escapeChar, char[] lineSeparator)` Deprecated.
	`CsvSchema(CsvSchema.Column[] columns, int features, char columnSeparator, int quoteChar, int escapeChar, char[] lineSeparator, int arrayElementSeparator, char[] nullValue)`
`protected`	`CsvSchema(CsvSchema.Column[] columns, int features, char columnSeparator, int quoteChar, int escapeChar, char[] lineSeparator, int arrayElementSeparator, char[] nullValue, Map<String,CsvSchema.Column> columnsByName)` Copy constructor used for creating variants using `withXxx()` methods.
`protected`	`CsvSchema(CsvSchema base, CsvSchema.Column[] columns)` Copy constructor used for creating variants using `sortedBy()` methods.
`protected`	`CsvSchema(CsvSchema base, int features)` Copy constructor used for creating variants for on/off features

Method Summary

Methods
Modifier and Type	Method and Description
`protected CsvSchema`	`_withFeature(int feature, boolean state)`
`boolean`	`allowsComments()`
`static CsvSchema.Builder`	`builder()`
`CsvSchema.Column`	`column(int index)`
`CsvSchema.Column`	`column(String name)`
`static CsvSchema`	`emptySchema()` Accessor for creating a "default" CSV schema instance, with following settings: Does NOT use header line Uses double quotes ('"') for quoting of field values (if necessary) Uses comma (',') as the field separator Uses Unix linefeed ('\n') as row separator Does NOT use any escape characters Does NOT have any columns defined
`int`	`getArrayElementSeparator()`
`String`	`getColumnDesc()` Method for getting description of column definitions in developer-readable form
`char`	`getColumnSeparator()`
`int`	`getEscapeChar()`
`char[]`	`getLineSeparator()`
`char[]`	`getNullValue()`
`int`	`getQuoteChar()`
`String`	`getSchemaType()`
`boolean`	`hasArrayElementSeparator()`
`Iterator<CsvSchema.Column>`	`iterator()`
`CsvSchema.Builder`	`rebuild()` Helper method for constructing Builder that can be used to create modified schema.
`int`	`size()`
`boolean`	`skipFirstDataRow()` Deprecated. Use `skipsFirstDataRow()` instead
`boolean`	`skipsFirstDataRow()`
`CsvSchema`	`sortedBy(Comparator<String> cmp)` Mutant factory method that will construct a new instance in which columns are sorted using given `Comparator` over column names.
`CsvSchema`	`sortedBy(String... columnNames)` Mutant factory method that will construct a new instance in which columns are sorted based on names given as argument.
`String`	`toString()`
`boolean`	`useHeader()` Deprecated. Use `usesHeader()` instead
`boolean`	`usesEscapeChar()`
`boolean`	`usesHeader()`
`boolean`	`usesQuoteChar()`
`CsvSchema`	`withAllowComments(boolean state)` Method to indicate whether "hash comments" are allowed for document described by this schema.
`CsvSchema`	`withArrayElementSeparator(char c)`
`CsvSchema`	`withColumnSeparator(char sep)`
`CsvSchema`	`withComments()` Method to indicate that "hash comments" ARE allowed for document described by this schema.
`CsvSchema`	`withEscapeChar(char c)`
`CsvSchema`	`withHeader()` Helper method for constructing and returning schema instance that is similar to this one, except that it will be using header line.
`CsvSchema`	`withLineSeparator(String sep)`
`CsvSchema`	`withNullValue(String nvl)`
`CsvSchema`	`withoutArrayElementSeparator()`
`CsvSchema`	`withoutColumns()`
`CsvSchema`	`withoutComments()` Method to indicate that "hash comments" are NOT allowed for document described by this schema.
`CsvSchema`	`withoutEscapeChar()`
`CsvSchema`	`withoutHeader()` Helper method for construcing and returning schema instance that is similar to this one, except that it will not be using header line.
`CsvSchema`	`withoutQuoteChar()`
`CsvSchema`	`withQuoteChar(char c)`
`CsvSchema`	`withSkipFirstDataRow(boolean state)`
`CsvSchema`	`withUseHeader(boolean state)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - FEATURE_USE_HEADER
```
protected static final int FEATURE_USE_HEADER
```
    See Also:
    Constant Field Values
  - FEATURE_SKIP_FIRST_DATA_ROW
```
protected static final int FEATURE_SKIP_FIRST_DATA_ROW
```
    See Also:
    Constant Field Values
  - FEATURE_ALLOW_COMMENTS
```
protected static final int FEATURE_ALLOW_COMMENTS
```
    See Also:
    Constant Field Values
  - DEFAULT_FEATURES
```
protected static final int DEFAULT_FEATURES
```
    See Also:
    Constant Field Values
  - DEFAULT_COLUMN_SEPARATOR
```
public static final char DEFAULT_COLUMN_SEPARATOR
```
    Default separator for column values is comma (hence "Comma-Separated Values")
    
    See Also:
    Constant Field Values
  - DEFAULT_ARRAY_ELEMENT_SEPARATOR
```
public static final char DEFAULT_ARRAY_ELEMENT_SEPARATOR
```
    Default separator for array elements within a column value is semicolon.
    
    See Also:
    Constant Field Values
  - DEFAULT_QUOTE_CHAR
```
public static final char DEFAULT_QUOTE_CHAR
```
    See Also:
    Constant Field Values
  - DEFAULT_NULL_VALUE
```
public static final char[] DEFAULT_NULL_VALUE
```
    By default, nulls are written as empty Strings ("")
  - DEFAULT_ESCAPE_CHAR
```
public static final int DEFAULT_ESCAPE_CHAR
```
    By default, no escape character is used -- this is denoted by int value that does not map to a valid character
    
    See Also:
    Constant Field Values
  - DEFAULT_LINEFEED
```
public static final char[] DEFAULT_LINEFEED
```
  - DEFAULT_USE_HEADER
```
public static final boolean DEFAULT_USE_HEADER
```
    By default we do NOT expect the first line to be header.
    
    See Also:
    Constant Field Values
  - DEFAULT_SKIP_FIRST_DATA_ROW
```
public static final boolean DEFAULT_SKIP_FIRST_DATA_ROW
```
    See Also:
    Constant Field Values
  - NO_COLUMNS
```
protected static final CsvSchema.Column[] NO_COLUMNS
```
  - _columns
```
protected final CsvSchema.Column[] _columns
```
    Column definitions, needed for optional header and/or mapping of field names to column positions.
  - _columnsByName
```
protected final Map<String,CsvSchema.Column> _columnsByName
```
  - _features
```
protected int _features
```
    Bitflag for general-purpose on/off features.
    
    Since:
    
    2.5
  - _columnSeparator
```
protected final char _columnSeparator
```
  - _arrayElementSeparator
```
protected final int _arrayElementSeparator
```
  - _quoteChar
```
protected final int _quoteChar
```
  - _escapeChar
```
protected final int _escapeChar
```
  - _lineSeparator
```
protected final char[] _lineSeparator
```
  - _nullValue
```
protected final char[] _nullValue
```
    Since:
    
    2.5
- Constructor Detail
  - CsvSchema
```
@Deprecated
public CsvSchema(CsvSchema.Column[] columns,
                    boolean useHeader,
                    boolean skipFirstDataRow,
                    char columnSeparator,
                    int quoteChar,
                    int escapeChar,
                    char[] lineSeparator)
```
    Deprecated.
  - CsvSchema
```
public CsvSchema(CsvSchema.Column[] columns,
         int features,
         char columnSeparator,
         int quoteChar,
         int escapeChar,
         char[] lineSeparator,
         int arrayElementSeparator,
         char[] nullValue)
```
    Since:
    
    2.5
  - CsvSchema
```
protected CsvSchema(CsvSchema.Column[] columns,
         int features,
         char columnSeparator,
         int quoteChar,
         int escapeChar,
         char[] lineSeparator,
         int arrayElementSeparator,
         char[] nullValue,
         Map<String,CsvSchema.Column> columnsByName)
```
    Copy constructor used for creating variants using withXxx() methods.
  - CsvSchema
```
protected CsvSchema(CsvSchema base,
         CsvSchema.Column[] columns)
```
    Copy constructor used for creating variants using sortedBy() methods.
  - CsvSchema
```
protected CsvSchema(CsvSchema base,
         int features)
```
    Copy constructor used for creating variants for on/off features
    
    Since:
    
    2.5
- Method Detail
  - builder
```
public static CsvSchema.Builder builder()
```
  - emptySchema
```
public static CsvSchema emptySchema()
```
    Accessor for creating a "default" CSV schema instance, with following settings:
    - Does NOT use header line
    - Uses double quotes ('"') for quoting of field values (if necessary)
    - Uses comma (',') as the field separator
    - Uses Unix linefeed ('\n') as row separator
    - Does NOT use any escape characters
    - Does NOT have any columns defined
  - rebuild
```
public CsvSchema.Builder rebuild()
```
    Helper method for constructing Builder that can be used to create modified schema.
  - withUseHeader
```
public CsvSchema withUseHeader(boolean state)
```
  - withHeader
```
public CsvSchema withHeader()
```
    Helper method for constructing and returning schema instance that is similar to this one, except that it will be using header line.
  - withoutHeader
```
public CsvSchema withoutHeader()
```
    Helper method for construcing and returning schema instance that is similar to this one, except that it will not be using header line.
  - withSkipFirstDataRow
```
public CsvSchema withSkipFirstDataRow(boolean state)
```
  - withAllowComments
```
public CsvSchema withAllowComments(boolean state)
```
    Method to indicate whether "hash comments" are allowed for document described by this schema.
    
    Since:
    
    2.5
  - withComments
```
public CsvSchema withComments()
```
    Method to indicate that "hash comments" ARE allowed for document described by this schema.
    
    Since:
    
    2.5
  - withoutComments
```
public CsvSchema withoutComments()
```
    Method to indicate that "hash comments" are NOT allowed for document described by this schema.
    
    Since:
    
    2.5
  - _withFeature
```
protected CsvSchema _withFeature(int feature,
                     boolean state)
```
  - withColumnSeparator
```
public CsvSchema withColumnSeparator(char sep)
```
  - withQuoteChar
```
public CsvSchema withQuoteChar(char c)
```
  - withoutQuoteChar
```
public CsvSchema withoutQuoteChar()
```
  - withEscapeChar
```
public CsvSchema withEscapeChar(char c)
```
  - withoutEscapeChar
```
public CsvSchema withoutEscapeChar()
```
  - withArrayElementSeparator
```
public CsvSchema withArrayElementSeparator(char c)
```
    Since:
    
    2.5
  - withoutArrayElementSeparator
```
public CsvSchema withoutArrayElementSeparator()
```
    Since:
    
    2.5
  - withLineSeparator
```
public CsvSchema withLineSeparator(String sep)
```
  - withNullValue
```
public CsvSchema withNullValue(String nvl)
```
    Since:
    
    2.5
  - withoutColumns
```
public CsvSchema withoutColumns()
```
  - sortedBy
```
public CsvSchema sortedBy(String... columnNames)
```
    Mutant factory method that will construct a new instance in which columns are sorted based on names given as argument. Columns not listed in argument will be sorted after those within list, using existing ordering.
    For example, schema that has columns:
```
"a", "d", "c", "b"
```
    ordered with schema.sortedBy("a", "b"); would result instance that columns in order:
```
"a", "b", "d", "c"
```
    Since:
    
    2.4
  - sortedBy
```
public CsvSchema sortedBy(Comparator<String> cmp)
```
    Mutant factory method that will construct a new instance in which columns are sorted using given Comparator over column names.
    
    Since:
    
    2.4
  - getSchemaType
```
public String getSchemaType()
```
    Specified by:
    
    getSchemaType in interface com.fasterxml.jackson.core.FormatSchema
  - usesHeader
```
public boolean usesHeader()
```
  - skipsFirstDataRow
```
public boolean skipsFirstDataRow()
```
  - allowsComments
```
public boolean allowsComments()
```
  - useHeader
```
@Deprecated
public boolean useHeader()
```
    Deprecated. Use usesHeader() instead
  - skipFirstDataRow
```
@Deprecated
public boolean skipFirstDataRow()
```
    Deprecated. Use skipsFirstDataRow() instead
  - getColumnSeparator
```
public char getColumnSeparator()
```
  - getArrayElementSeparator
```
public int getArrayElementSeparator()
```
  - getQuoteChar
```
public int getQuoteChar()
```
  - getEscapeChar
```
public int getEscapeChar()
```
  - getLineSeparator
```
public char[] getLineSeparator()
```
  - getNullValue
```
public char[] getNullValue()
```
    Since:
    
    2.5
  - usesQuoteChar
```
public boolean usesQuoteChar()
```
  - usesEscapeChar
```
public boolean usesEscapeChar()
```
  - hasArrayElementSeparator
```
public boolean hasArrayElementSeparator()
```
    Since:
    
    2.5
  - iterator
```
public Iterator<CsvSchema.Column> iterator()
```
    Specified by:
    
    iterator in interface Iterable<CsvSchema.Column>
  - size
```
public int size()
```
  - column
```
public CsvSchema.Column column(int index)
```
  - column
```
public CsvSchema.Column column(String name)
```
  - getColumnDesc
```
public String getColumnDesc()
```
    Method for getting description of column definitions in developer-readable form
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class CsvSchema

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

FEATURE_USE_HEADER

FEATURE_SKIP_FIRST_DATA_ROW

FEATURE_ALLOW_COMMENTS

DEFAULT_FEATURES

DEFAULT_COLUMN_SEPARATOR

DEFAULT_ARRAY_ELEMENT_SEPARATOR

DEFAULT_QUOTE_CHAR

DEFAULT_NULL_VALUE

DEFAULT_ESCAPE_CHAR

DEFAULT_LINEFEED

DEFAULT_USE_HEADER

DEFAULT_SKIP_FIRST_DATA_ROW

NO_COLUMNS

_columns

_columnsByName

_features

_columnSeparator

_arrayElementSeparator

_quoteChar

_escapeChar

_lineSeparator

_nullValue

Constructor Detail

CsvSchema

CsvSchema

CsvSchema

CsvSchema

CsvSchema

Method Detail

builder

emptySchema

rebuild

withUseHeader

withHeader

withoutHeader

withSkipFirstDataRow

withAllowComments

withComments

withoutComments

_withFeature

withColumnSeparator

withQuoteChar

withoutQuoteChar

withEscapeChar

withoutEscapeChar

withArrayElementSeparator

withoutArrayElementSeparator

withLineSeparator

withNullValue

withoutColumns

sortedBy

sortedBy

getSchemaType

usesHeader

skipsFirstDataRow

allowsComments

useHeader

skipFirstDataRow

getColumnSeparator

getArrayElementSeparator

getQuoteChar

getEscapeChar

getLineSeparator

getNullValue

usesQuoteChar

usesEscapeChar

hasArrayElementSeparator

iterator

size

column

column

getColumnDesc

toString